L-carnitine in dialysis patients.

Hemodialysis (HD) patients often have low serum concentrations of free L-carnitine and decreased skeletal muscle stores. As L-carnitine is an essential cofactor in fatty acid and energy metabolism, it is possible that abnormal carnitine metabolism in dialysis patients may be associated with clinical problems such as skeletal myopathies, intradialytic symptoms, reduced cardiac function, and anemia. Studies have shown that L-carnitine supplementation in HD patients improves several complications seen in dialysis patients, including cardiac complications (arrhythmias, reduced output, low cardiothoracic ratio), limitation of exercise capacity, increased intradialytic hypotension, and muscle symptoms. The most promising results have been noted in the treatment of erythropoietin-resistant anemia. Routine administration of L-carnitine to all dialysis patients is not recommended at this time; however, a therapeutic trial of L-carnitine can be useful in symptomatic patients with certain clinical features unresponsive to the usual measures. These include intradialytic muscle cramps and hypotension, asthenia, cardiomyopathy, lowered ejection fraction, muscle weakness or myopathy, reduced oxygen consumption, and anemia requiring large doses of EPO.